Percentage energy loss (mechanical energy) problem

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poopandpee
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Homework Statement


Problem: An object with mass 2.0 kg slides down a low-friction incline and its speed measured at the bottom is 2.7 m/s. The object starts sliding at a height of 0.50 m over the tabletop and its speed is measured 0.10 m over the tabletop. How big is the percentage energy loss?

Homework Equations

The Attempt at a Solution


My attempt: I've tried using this formula: mgh(0) + W(other forces) = 0.5mv2, where m=2.0 kg, h=0.4 m, and v=2.7 Then I found W(other forces) and divided it by mgh(0). However, that did not give a right answer. Any suggestions?
 

Discussion

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The sign of the energy loss is a bit questionable but overall the approach is good. Maybe some mistake in the calculations? You didn't show them.
 
Did you remember to multiply by 100 to convert to %?
 
You shouldn't divide by the other work, if your equation above is correct you should subtract mgh(0) to get W alone
 
NateTheGreatt77 said:
You shouldn't divide by the other work, if your equation above is correct you should subtract mgh(0) to get W alone
That appears to be what @poopandpee did before dividing:
poopandpee said:
Then I found W(other forces)
As others have posted, the method sounds correct, but we need to see the details.